U.S. Provisional Application No. 61/220,692, filed Jun. 26, 2009, and U.S. Provisional Application No. 61/222,272, filed Jul. 1, 2009, are incorporated herein by reference in their entirety.
Pipe couplers are well known for use in coupling pipes in sealed relation to other pipes, tees and other fittings, to provide a continuous sealed passage for the flow of fluids, including both liquids and solids, such as, but not limited to, chemicals, food products, and particulates such as cement. Such couplers are commonly used in piping systems on bulk materials transports and hoppers, for conveying fluid carried thereby. Desirable feature of such couplers include the ability to quick and easy couple and uncouple, to enable disassembly of pipes or removal of pipes from tees and the like, for purposes such as inspection, cleaning and repair. For instance, after travel to a delivery site and unloading, it may be required to uncouple the pipes of a transport or hopper for cleaning and preparing for transporting a different material. Or, it may be found that a pipe has become clogged, so as to require uncoupling for removal of the clog. Or a coupler gasket may be damaged or otherwise leaking, so as to require replacement.
Reference, Sisk U.S. Pat. Nos. 5,540,465 and 5,722,666, and U.S. Patent Publication No. 2005/0248098; Burian et al., U.S. Pat. No. 7,165,789; and Heelan et al. U.S. Patent Publication No. 2008/0136167, which disclose a variety of known hinged pipe couplers or clamp assemblies, and gaskets, some of which gaskets are annular, and some of which are semi-circular.
Problems commonly encountered when coupling pipes and fittings on bulk transports and hoppers, include that the coupler gasket can be improperly seated in the coupler as the pipes or fittings are being coupled. The pipes can be heavy, particularly when filled or partially filled with material, and thus can be hard to handle and position for coupling by one person, which can contribute to this problem. This can be particularly problematic with some couplers that require the bail of the coupler to be disconnected from the opposite side of the coupler to open the coupler sufficiently to place it on the pipe ends to be coupled, e.g., Sisk et al. and Heelan et al. patents and publications, or wherein the bail can remain connected, but can inadvertently disconnect, e.g., Burian et al. patent.
Further in the above regard, some couplers, such as that disclosed in U.S. Pat. No. 7,165,789, are designed for use with a split gasket which is positively retained by the coupler only at the ends. As a result, during coupling, as the ends of the coupler and gasket are brought together, the gasket is pulled or drawn about the ends of the pipes or pipe and fitting being coupled, to bring the split gasket ends together in sealed relation. If the gasket drags or sticks as it is pulled about the pipe ends, sealing pressure about the circumference of the coupler may be uneven. Also, because the gasket is pulled together from the ends being brought together, the opposing ends of the gasket may be in a tensile state when brought together as the coupler is closed about pipe ends being coupled, so as to form only a partial or poorly sealed condition, so as to have more of a tendency to leak.
As another problem, when uncoupling a coupler, the gasket can stick to the pipe, and/or the coupler can stick to the gasket, making removal difficult, and if force is applied, for instance, using a hammer or mallet to open the coupler, the gasket can be torn or otherwise damaged. And, if a split gasket is unavailable and instead it is attempted to use an annular gasket, the cavities are sufficiently large, particularly in sideward extent, such that annular gasket can deform into the cavities so as to leak.
Further, if the clamping mechanism of many of the known couplers is improperly adjusted, more force than normally necessary may be needed to close the coupler. Rather than properly adjust the coupler, some personnel will attempt to force the coupler closed, for instance by striking it, or using additional leverage on the handle of the clamping mechanism, e.g., by extending the length using an extender or cheater bar. This can damage the clamp, e.g., break the handle of the mechanism. And similarly, if the coupler clamping mechanism is stuck closed, some persons will attempt to pry it open by using additional leverage. This can also damage the coupler or clamping mechanism.
Regarding adjusting the clamping mechanism, some couplers, such as those of the Sisk et al. patent and publication identified above, require adjusting nuts on opposite ends of a U-shaped bail assembly, which can be time consuming and discouraging to personnel to adjust. Others, such as the Burian et al. and Heelan et al. couplers, use a single bail, but the adjusting nut is located so as to be very difficult to access, which also discourages adjustment. As a result, it has been found that many of the known couplers in use in the field are improperly adjusted, so as to be susceptible to leakage and damage.
Still further, some of the known couplers have handles that are susceptible to pinching a user's hand when closed, due to close proximity of the handle to the coupler body.
Accordingly, what is sought is a pipe coupler and gasket that overcomes one or more of the problems and shortcomings set forth above.